Hydrological Simulation of Flood Disaster in Savitri River, Maharashtra

A brief hydrological modeling study has been carried out in the Savitri River, Maharashtra for approximate forecasting of flood discharges in the rivers to study the impact of flood disaster using the space based inputs, and rainfall from IMD. Geographical description of Savitri River is shown in the figure 1.

Fig 1. Geographical description of the study area

For hydrological modeling in Savitri River, IMD rainfall of 8-00 AM, 2^nd August to 8-00 AM of 3^rd August was used.

SRTM DEM, landuse land cover grid (derived from IRS P6 satellite data of 2010) of the study area, and soil textural grids were used in deriving the input parameters for the study. Hydrograph computed at the final outlets of Savitri is shown in the figures 2.

Computed peak discharges are approximately 1683 cumecs in the Savitri River. The model is un-calibrated and therefore calculations may have an error of + or - 25%.

Fig. 2 Flood hydrograph computed at final outlet of Vamsadhara River

Flood inundation simulations were done using high resolution processed Digital Terrain Model (CARTO DTM of 10 m resolution, msl datum with height accuracy of 3 to 4 m). River cross sections profiles were extracted at regular intervals along Savitri River, river longitudinal profile, and other topographic parameters were extracted using the DEM and landuse. The above computed flood hydrographs of the river were used in simulating the approximate flood inundation and in computing the dynamics of flow. Simulated flood inundation during the maximum flood is shown in the figure 3.

Bare earth elevation model is used to approximate ground level inundation scenario without considering urban infrastructure. Hence, the simulation results are approximate and can give overall picture of flood scenario.

Fig.3 Flood inundation simulations (in Savitri River)